Rehabilitation of edentulous mandibles by means of five TiUnite implants after one-stage surgery: a 1-year retrospective study of 90 patients

Abstract

Background: Recently, the present team reported the 1-year data of one-stage surgery and mainly early loading performed in edentulous mandibles using 750 turned Brånemark System implants in 152 patients.

Purpose: The aim of the present investigation was to retrospectively evaluate the 1-year results of the same treatment technique, using Brånemark System implants with an oxidized surface (TiUnite, Nobel Biocare AB, Göteborg, Sweden). The outcome was compared with that of the former study (control) on turned implants.

Materials and methods: The present study involved 90 individuals with 450 TiUnite implants of mainly the Brånemark System Mark III design, placed in edentulous mandibles and using one-stage surgery. The prosthetic procedure was commenced as a mean 8 days after the surgical intervention. Intraoral radiographs were obtained at prosthesis insertion and at the 1-year annual checkup. Failure rates of test and control groups were compared by means of the chi-square test.

Results: No implants were found to be mobile up to and including the first annual checkup, resulting in an implant cumulative survival rate (CSR) of 100%. The corresponding CSR for the control group was 97.5%, and this difference in implant survival was statistically significant when analyzed with the chi-square test (p < .001). A statistically significant difference was also demonstrated (p < .01) when conducting the same statistical analysis on the patient level. The mean marginal bone resorption during the first year of function was 0.49 mm (SD 0.56), and the corresponding figures for the control study were 0.39 mm (SD 0.46). The central TiUnite implant, that is, the one placed in or in close relation to the symphyseal region showed significantly more bone loss (p < .05) than the corresponding central turned implant of the control study. Distally positioned test implants demonstrated less marginal bone loss than the corresponding central one.

Conclusions: The outcome of 450 TiUnite implants placed in 90 patients with edentulous mandibles, of which 380 implants in 76 patients were followed for 1 year, showed an implant CSR of 100%. The figure was significantly different from the control study result of 97.5% on turned surface implants. The levels of marginal bone were close to identical for test and control implants at the 1-year checkup.